Restricted Expansion Dissector

ABSTRACT

A surgical apparatus is disclosed that is configured and dimensioned to create an internal surgical worksite. The surgical apparatus includes a dissection element that is repositionable between an unexpanded condition, wherein the dissection element defines a first outer transverse cross-sectional dimension, and an expanded condition, wherein the dissection element defines a second, larger outer transverse cross-sectional dimension. The surgical apparatus further includes a restrictor that is in contact with the dissection element in order to restrict expansion of the dissection element in at least one direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of, and priority to, U.S.Provisional Patent Application Ser. No. 61/833,610, filed Jun. 11, 2013,which is hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure generally relates to an apparatus and method forcreating a surgical worksite inside a patient's body through an openingin tissue. More specifically, the present disclosure relates to asurgical apparatus that includes an expandable dissection element forseparating adjacent tissue layers, and corresponding methods of use.

BACKGROUND

During certain surgical procedures, it may become necessary to separateadjacent tissue layers in order to create an internal surgical worksite.Various dissectors useful in the formation of such worksites are known,and typically include an expandable dissection element, e.g., a balloon,that is supported on the distal end of a tube. A need remains, however,for increased control over the expansion of such dissection elements inorder to selectively limit tissue displacement during formation of thesurgical worksite. The present disclosure addresses this need, amongothers, and describes a surgical apparatus including an expandabledissection element that allows for an increased level of control overexpansion of the dissection element in one or more directions.

SUMMARY

In one aspect of the present disclosure, a surgical apparatus isdisclosed that is configured and dimensioned to create an internalsurgical worksite. The surgical apparatus includes a dissection element,and a restrictor that is in contact with the dissection element.

The dissection element is repositionable between an unexpandedcondition, wherein the dissection element defines a first outertransverse cross-sectional dimension, and an expanded condition, whereinthe dissection element defines a second, larger outer transversecross-sectional dimension. The restrictor element is configured anddimensioned to restrict expansion of the dissection element in at leastone direction.

The dissection element may be at least partially formed from a materialpermitting at least some light to pass therethrough. For example, thedissection element may include translucent portions, transparentportions, opaque portions, or combinations thereof.

The restrictor may be configured to restrict expansion of the dissectionelement such that the dissection element defines a generally planarconfiguration in the expanded condition, according to the definitionprovided herein.

The dissection element and the restrictor may have differentresiliencies.

The dissection element may be at least partially formed from a firstmaterial, and the restrictor may be at least partially formed from asecond material different than the first material. For example, thedissection element may be at least partially formed from a materialhaving a first durometer, and the restrictor may be at least partiallyformed from a material having a second, greater durometer.

The dissection element may be at least partially formed from urethane,and the restrictor may be at least partially formed from ripstop nylon.

The dissection element and the restrictor may be configured as discretestructures.

The restrictor may be positioned externally of the dissection element.Alternatively, the restrictor may be positioned internally within thedissection element, or between adjacent layers of the material(s) fromwhich the dissection element is formed.

The restrictor may include a pair of first arms and a pair of secondarms, wherein the pair of first arms are secured together, and the pairof second arms are secured together. For example, the pair of first armsmay be welded together, and the pair of second arms may be weldedtogether.

The pair of first arms and the pair of second arms may also be securedto the material from which the dissection element is formed.

The restrictor may define a contour corresponding to that defined by thedissection element in the expanded condition. For example, the arms ofthe restrictor may include portions that are curvate in configuration.

The dissection element and the restrictor may be at least partiallyformed from the same material, e.g., urethane, and may be integrallyformed. In such embodiments, the dissection element may define a firstthickness, and the restrictor element may define a second, greaterthickness.

In another aspect of the present disclosure, a restrictor is disclosedthat is configured for use with an expandable dissection element duringthe creation of an internal surgical worksite. The restrictor includes afirst portion including first and second arms, and a second portionconnected to the first portion that also includes first and second arms.The first arm of the first portion is secured to the first arm of thesecond portion, and the second arm of the first portion is secured tothe second arm of the second portion such that the restrictor restrictsexpansion of the dissection element in at least one direction.

The restrictor may be configured and dimensioned to restrict expansionof the dissection element such that the dissection element defines agenerally planar configuration in the expanded condition.

The first arm of the first portion may be welded to the first arm of thesecond portion, and the second arm of the first portion may be welded tothe second arm of the second portion.

The first and second arms of the first portion, and the first and secondarms of the second portion, may be secured to the material from whichthe dissection element is formed.

The restrictor may define a contour corresponding to that defined by thedissection element upon expansion. For example, the arms of therestrictor may include portions that are curvate in configuration.

The restrictor may be at least partially formed from a material lessresilient than that included in the dissection element, e.g., thematerial from which the dissection element is formed.

The restrictor may be positioned externally of the dissection element.Alternatively, the restrictor may be positioned internally within thedissection element, or between adjacent layers of the material(s) fromwhich the dissection element is formed.

The materials of construction used in formation of the restrictor andthe dissection element may be different. For example, the restrictor maybe at least partially formed from a material having a higher durometerthan that included in the dissection element, e.g., the material fromwhich the dissection element is formed.

The restrictor may be at least partially formed from ripstop nylon.

The restrictor may be at least partially formed from a materialpermitting at least some light to pass therethrough.

In yet another aspect of the present disclosure, a method of performinga surgical procedure is disclosed that includes inserting a surgicalapparatus into an opening in tissue, expanding a dissection element ofthe surgical apparatus to separate adjacent layers of the tissue to forman internal surgical worksite, and mechanically restricting expansion ofthe dissection element in at least one direction via a restrictor incontact with the dissection element subjecting the dissection element toan inwardly directed force.

Expanding the dissection element may include communicating fluid intothe dissection element, e.g., through a cannula assembly supporting thedissection element.

Mechanically restricting expansion of the dissection element may includelimiting the dissection element to a generally planar configuration uponexpansion.

The disclosed method may further include visualizing the internalsurgical worksite through the dissection element. For example,visualizing the internal surgical worksite may include passing avisualization instrument into the dissection element, e.g., through acannula assembly supporting the dissection element.

In another aspect of the present disclosure, a surgical apparatus isdisclosed that is configured and dimensioned to create an internalsurgical worksite. The surgical apparatus includes a dissection elementthat is repositionable between an unexpanded condition, wherein thedissection element defines a first outer transverse cross-sectionaldimension, and an expanded condition, wherein the dissection elementdefines a second, larger outer transverse cross-sectional dimension.

The dissection element may be at least partially formed from one or morelayers of material restricting expansion of the dissection element inone or more dimensions beyond a predetermined measure. For example, theone or more layers of material may restrict expansion of the dissectionelement beyond a particular volume, or may restrict expansion of thedissection element such that the expansion element defines a particularconfiguration in the expanded condition.

The dissection element may be formed from a single material, e.g.,ripstop nylon. Alternatively, the dissection element may be at leastpartially formed from one or more layers of film having a high modulusof elasticity, e.g., high durometer polyurethane, polyethylene, ormylar.

Alternatively, the dissection element may be formed from a layer offirst material that is reinforced with a second, different material,e.g., a layer of urethane film that is reinforced with ripstop nylon orflashspun high-density polyethylene fibers.

Alternatively, the dissection element may be formed from a first layerof material that is secured to a second layer of material at one or morejunction points that restrict expansion of the dissection element indirections transverse, e.g., perpendicular, to the one or more junctionpoints.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial cross-sectional illustration showing the use of adissector assembly including an expandable dissection element and arestrictor in accordance with one embodiment of the present disclosureto create an internal worksite during a surgical procedure;

FIG. 2 illustrates the dissector assembly seen in FIG. 1 removed fromthe internal worksite;

FIG. 3 illustrates an alternate embodiment of the presently discloseddissector assembly;

FIG. 4 is a cross-sectional illustration of the dissection element andthe restrictor seen in FIG. 1 along line 4-4;

FIGS. 5 and 6 are cross-sectional illustrations of alternate embodimentsof the presently disclosed dissection element and restrictor;

FIG. 7 is a plan view of the restrictor seen in FIGS. 1 and 2;

FIG. 7A is a plan view of an alternate embodiment of presently disclosedrestrictor;

FIG. 8 is a plan view of an alternate embodiment of the restrictor seenin FIG. 7;

FIGS. 9-11 are cross-sectional illustrations of alternate embodiments ofthe presently disclosed dissection element and restrictor;

FIG. 12 is a rear view of an alternate embodiment of the presentlydisclosed dissection element;

FIG. 13 is a top view of the embodiment of the dissection element seenin FIG. 12;

FIG. 14 is a cross-sectional illustration of the dissection element seenin FIG. 13 along line 14-14; and

FIG. 15 is a cross-sectional illustration of another embodiment of thepresently disclosed dissection element.

DETAILED DESCRIPTION

Embodiments of the present disclosure will now be described in detailwith reference to the drawings, wherein like reference numerals identifysimilar or identical elements. As used herein, the term “patient” refersto a human or animal patient, and the term “clinician” refers to adoctor, nurse, support personnel, or other care provider. While thedevices, systems, and methodologies described herein are discussed andillustrated in the context of an abdominal procedure, the principles ofthe present disclosure are equally applicable to other surgicalprocedures performed in alternate locations within a patient's body,e.g., vascular procedures, cardiac procedures, and urinary procedures.

FIGS. 1 and 2 illustrate a dissector assembly 1000 in accordance withthe principles of the present disclosure that includes a cannulaassembly 100, shown in communication with a fluid source 200, and anexpandable dissection element 300, e.g., a balloon, bladder, or thelike, that is supported by the cannula assembly 100. The dissectorassembly 1000 is configured and dimensioned to create, and facilitateaccess to, an internal worksite W within a patient. For example, thedissector assembly 1000 may be utilized beneath a patient's externaltissue T to form the internal worksite W between adjacent tissue layersTL₁, TL₂.

The cannula assembly 100 includes a shaft 102 having a proximal end 104that is in communication with the fluid source 200, and a distal end 106that supports the dissection element 300. The shaft 102 includes a lumen108 extending therethrough that facilitates the communication of fluid,e.g., a liquid, a gas, or a combination thereof, from the fluid source200 into the dissection element 300 to permit expansion thereof. Toregulate the flow of fluid from the fluid source 200 to the dissectionelement 300, the cannula assembly 100 may include one or more valves(not shown).

The dissection element 300 is repositionable from an initial, unexpandedcondition to an expanded condition via the communication of fluid intothe dissection element 300, during which time, the dissection element300 is enlarged in three dimensions, i.e., along the X, Y, and Z axes(FIG. 2). In the unexpanded condition, the dissection element 300defines a first outer transverse cross-sectional dimension, and in theexpanded condition, (FIGS. 1 and 2), the dissection element 300 isenlarged to define a second outer transverse cross-sectional dimensionlarger than the first outer transverse cross-sectional dimension. Forexample, in moving from the unexpanded condition to the expandedcondition, the dimensions of the dissection element 300 may be increasedalong one or more of the X, Y, and Z axes (FIG. 2).

In addition to the configurations seen in FIGS. 1 and 2, the dissectionelement 300 may be configured to achieve any desired shape in theexpanded condition, dependent upon the particular requirements of thesurgical procedure in which the dissector assembly 1000 is employed. Forexample, in the expanded condition, the dissection element 300 may beconfigured as illustrated in FIG. 3, or alternatively, the dissectionelement 300 may define a circular configuration, an oval configuration,a kidney-shaped configuration, a triangular configuration, a toroidalconfiguration, etc. The dissection element 300 may be formed from anymaterial of construction suitable for the intended purpose of permittingexpansion of the dissection element 300 in the manner described herein.

In one embodiment of the disclosure, in order to facilitatevisualization through the dissection element 300, e.g., during theseparation of tissue and formation of the internal worksite W (FIG. 1),the dissection element 300 may be formed, either in whole or in part,from a material permitting at least some light to pass therethrough,e.g., clear urethane. For example, the dissection element 300 mayinclude translucent portions, transparent portions, or combinationsthereof, as well as opaque portions.

With reference now to FIG. 4, in one embodiment, the dissection element300 includes, e.g., is formed from, one or more layers 302 of materialthat are secured together to define an interior space S. For example, inthe embodiment illustrated in FIG. 4, the dissection element 300 isformed by securing together two layers 302 _(A), 302 _(B) of material atthe perimeters thereof, or any other suitable location. The layers 302_(A), 302 _(B) of material may be secured together through any suitablemanufacturing procedure, including, but not limited to, welding viaimpulse, laser, or RF, or through the use of an adhesive. Alternatively,the layers 302 may be formed monolithically, either partially orentirely.

In order to restrict expansion of the dissection element 300, andachieve a desired configuration in the expanded condition, the dissectorassembly 1000 further includes a restrictor 400 (FIGS. 1, 2, 4, and 7).In the embodiment of the disclosure illustrated in FIGS. 1, 2, 4, and 7,the restrictor 400 is provided as an additional, discrete component ofthe dissector assembly 1000 that is in contact with, e.g., secured to,the dissection element 300. For example, the restrictor 400 may besecured to an outer surface 304 of the dissection element 300, eitherfixedly or removably, so as to at least partially envelop the dissectionelement 300, as seen in FIGS. 1, 2, and 4. Alternatively, as seen inFIG. 5, the restrictor 400 may be secured to an internal surface 306 ofthe dissection element 300 such that the restrictor 400 is positionedwithin the interior space S. In another embodiment of the disclosure,which is illustrated in FIG. 6, it is envisioned that the restrictorelement 400 may be embedded between adjacent layers 302 _(A), 302 _(B)and between adjacent layers 302 _(C), 302 _(D) of the material fromwhich the dissection element 300 is formed. Alternatively, therestrictor 400 may be monolithically formed with at least one of thelayers 302 of the dissection element 300.

The restrictor 400 may entirely prevent expansion of one or moreportions of the dissection element 300 in one or more directions. It isalso contemplated, however, that the restrictor 400 may simply limitexpansion of one or more potions of the dissection element 300, andpermit a certain degree of expansion of the one or more portions.

The resiliency of the restrictor 400 may be less than that of thedissection element 300. For example, the dissection element 300 may beat least partially formed from a first material having a firstdurometer, e.g., clear urethane, and the restrictor 400 may be at leastpartially formed from a second, different material having a second,higher durometer, and/or increased rigidity, and/or decreasedflexibility, e.g., ripstop nylon, a metallic alloy, a textile, orcombinations thereof. Alternatively, it is contemplated that portions ofthe restrictor 400 may include the same material as the dissectionelement 300.

The reduced resiliency of the restrictor 400 compared to that of thedissection element 300 may be accomplished in various ways. For example,the restrictor 400 may include more layers 302 of material than thedissection element 300, or the restrictor 400 may be of a greaterthickness than the dissection element 300. Additionally, oralternatively, the restrictor 400 may include a substantially rigidmaterial, or may define a perimeter having lesser flexibility than theremainder of the restrictor 400.

The reduced resiliency of the restrictor 400 compared to that of thedissection element 300 allows the restrictor 400 to selectively inhibitexpansion of the dissection element 300 along one or more of the axes X,Y, Z (FIG. 2), dependent upon the particular configuration of therestrictor 400, and the orientation of the restrictor 400 in relation tothe dissection element 300. As seen in FIG. 4, for example, therestrictor 400 may be configured, dimensioned, and positioned torestrict expansion of the dissection element 300 along the Y axis inorder to prevent the dissection element 300 from assuming a sphericalconfiguration, and instead, realize a flattened, oblong, or otherwisegenerally planar configuration in the expanded condition. Throughout thepresent disclosure, the term “generally planar” is used to describe theconfiguration of the dissection element 300 in the expanded condition,in which the dissection element 300 may not be perfectly planar inconfiguration, and may include both curvilinear portions and straightportions. For example, dependent upon the particular configuration ofthe restrictor 400, the portions of the dissection element 300immediately adjacent to, or in contact with, the restrictor 400 may beeither flat, or may include a slight curvature, e.g., less than 20°,whereas those portions of the dissection element 300 further from therestrictor 400 may include a greater curvature. In the context of theparticular embodiment show in FIG. 4, the portions of the dissectionelement 300 immediately adjacent to the restrictor 400 are generallyflat, with a relatively constant dimension along the Y axis, in contrastto those portions of the dissection element 300 spaced outwardly fromthe restrictor 400, i.e., along the X axis, which include a morevariable dimension along the Y axis.

In one embodiment, the restrictor 400 defines a contour corresponding tothat defined by the outer surface 304 (FIG. 4) of the dissection element300. For example, with reference to FIG. 7, which illustrates therestrictor 400 separated from the dissection element 300, the restrictor400 may include first and second portions 402 _(A), 402 _(B),respectively, wherein the first portion 402 _(A) includes a first arm404 _(A1), a second arm 404 _(A2), and a third arm 404 _(A3), and thesecond portion 402 _(B) includes a first arm 404 _(B1), a second arm 404_(B2), and a third arm 404 _(B3). In order to mimic the contour definedby the dissection element 300 in the expanded condition, each of thearms 404 _(A1), 404 _(A2), and 404 _(A3) of the first portion 402 _(A),and the arms 404 _(B1), 404 _(B2), and 404 _(B3) of the second portion402 _(B), may include a curvature matching that defined by thedissection element 300, as can be appreciated through reference to FIGS.1 and 2.

To secure the restrictor 400 relative to the dissection element 300, thearms 404 _(A1), 404 _(B1) and the arms 404 _(A2), 404 _(B2) may besecured together through any suitable manufacturing procedure,including, but not limited to, welding using impulse, laser, or RF, orthrough the use of an adhesive. To further secure the restrictor 400relative to the dissection element 300, one or more portions of therestrictor 400, e.g., one or more of the arms 404 _(A1), 404 _(A2), 404_(B1), 404 _(B2), 404 _(C1), 404 _(C2), may also be secured to, ormonolithically formed with, the material from which the dissectionelement 300 is formed, e.g., the layers 302 _(A), 302 _(E) (FIG. 4).

In one embodiment, such as that represented in FIG. 7, the restrictor400 may be formed from a single piece of material in order to eliminateseparation between the arms 404 _(A3), 404 _(B3) of the respective firstand second portions 402 _(A), 402 _(B). In such embodiments, inpositioning the restrictor 400 relative to the dissection element 300,the arms 404 _(A3), 404 _(B3) may be bent or deformed as required.

In another embodiment, such as that represented in FIG. 8, one or moreof the arms, e.g., the arms 404 _(A3), 404 _(B3), may be connected toone another via a hinge element 406, e.g., a living hinge 408.

The restrictor 400 may include any number of arms, or be configured inany manner, which facilitates the intended purpose of restrictingexpansion of the dissection element 300 in one or more directions. Therestrictor 400 may be positioned such that portions of the restrictor400 are positioned adjacent portions of the dissection element 300 thatare capable of greater expansion than other portions of the dissectionelement 300.

In another embodiment, which is illustrated in FIG. 7A, the restrictor400 includes a single body portion 402 having a first arm 404 _(A1), asecond arm 404 _(A2), and a third arm 404 _(A3), and is configured anddimensioned for positioning adjacent one side of the dissection element300 only, rather than adjacent opposing sides of the dissection element300, e.g., as illustrated in FIG. 4, for example.

The restrictor 400 may be of varying rigidity or flexibility, forexample, via the inclusion of various material(s) of construction, byvarying the thicknesses of the materials of construction, and/or byvarying the number of layers of material. For example, with reference toFIG. 2, the restrictor 400 may be of greater rigidity at the locationwherein the arms 404 _(A1), 404 _(A2), 404 _(A3) intersect relative tothe rigidity of the arms 404 _(A1), 404 _(A2), 404 _(A3) themselves.Alternatively, one or more of the arms 404 _(A1), 404 _(A2), 404 _(A3)may be of different flexibility.

With reference now to FIGS. 1, 2, and 4, a method of performing asurgical procedure with the dissector assembly 1000 will be discussed.Initially, the dissector assembly 1000 is advanced through an opening 0in the tissue T, which may be either naturally occurring or surgicallycreated, such that the dissection element 300 is positioned internally,beneath the tissue T, in a desired location. Thereafter, fluid iscommunicated into the dissection element 300, e.g., through the cannulaassembly 100, to move the dissection element 300 into the expandedcondition seen in FIG. 1. During expansion of the dissection element300, the adjacent tissue layers T₁, T₂ are separated in order to createthe internal worksite W. As the dissection element 300 is expanded, aninwardly directed force F (FIG. 4) is applied to the dissection element300 by the restrictor 400 in order to inhibit expansion of thedissection element in at least one direction. For example, in theparticular embodiment illustrated in FIG. 4, the restrictor 400 inhibitsexpansion of the dissection element 300 along the Y axis, therebylimiting tissue displacement along the Y axis, such that the dissectionelement 300 defines the illustrated generally planar configuration inthe expanded condition.

During expansion of the dissection element 300, an endoscope (notshown), or other suitable viewing instrument may be inserted into thedissection element 300, e.g., via the cannula assembly 100, in order tofacilitate visualization of the tissue, e.g., the internal worksite W.As mentioned above, the dissection element 300 may include translucentportions, transparent portions, or combinations thereof, whereby thetissue, e.g., the internal worksite W, can be visualized directlythrough the dissection element 300.

Following creation of the internal worksite W, fluid can be withdrawnfrom the dissection element 300 so as to return to the dissectionelement 300 to the unexpanded condition, and the dissector assembly 1000can be withdrawn from the patient.

With reference now to FIGS. 9-11, alternate embodiments of thedissection element and the restrictor will be discussed, which areidentified by the reference characters 1300 and 1400, respectively. Thedissection element 1300 and the restrictor 1400 are identical to thedissection element 300 and the restrictor 400 discussed above withrespect to FIGS. 1, 2, and 4, for example, but for the differencesdescribed below.

In the embodiments shown, the restrictor 1400 is integrally formed withthe dissection element 1300, and is formed from the same material ofconstruction as the dissection element 1300, e.g., clear urethane. Inorder to reduce the resiliency of the restrictor 1400 relative to thedissection element 1300, the restrictor 1400 defines an increasedthickness, i.e., a larger cross-sectional dimension along the axis inwhich limited expansion of the dissection element 1300 is desired. Forexample, with reference to FIG. 9, the thickness T₁ of the restrictor1400 is increased in relation to the thickness T₂ of the dissectionelement 1300 along the Y axis in order to limit expansion of thedissector element 1300 along the Y axis. Since it may be desirable tolimit expansion of the dissector element 1300 in additional dimensions,in additional embodiments of the disclosure, the thickness T₁ of therestrictor 1400 may be increased in additional locations. For example,with reference to FIG. 10, the thickness T₁ of the restrictor 1400 maybe increased in relation to the thickness T₂ of the dissection element1300 to limit expansion of the dissector element 1300 along the X axisin addition to the Y axis.

It is envisioned that the restrictor 1400 may extend outwardly from thedissection element 300, as seen in FIGS. 9 and 10, for example.Alternatively, it is envisioned that the restrictor 1400 may extendinwardly into the interior space S defined within the dissection element1300, as seen in FIG. 11, for example.

With reference now to FIGS. 12-14, another embodiment of the dissectionelement will be discussed, which is identified by the referencecharacter 2300. The dissection element 2300 is identical to thedissection element 300 discussed above with respect to FIGS. 1, 2, and4, for example, but for the differences described below.

The dissection element 2300 is formed from one or more materials ofconstruction that inherently restrict expansion of the dissectionelement 2300 in one or more directions beyond a certain predeterminedmeasure. For example, the materials of construction may restrictexpansion of the dissection element 2300 beyond a particular volume, ormay restrict expansion of the dissection element 2300 such that theexpansion element 2300 defines a particular configuration in theexpanded condition.

The particular materials of construction for the dissection element 2300obviate the need for a separate, discrete restrictor element, and thus,reduce the cost and complexity of manufacture. For example, in oneembodiment, the dissection element 2300 may be formed entirely fromripstop nylon, or from one or more layers of film having a high modulusof elasticity, e.g., high durometer polyurethane, polyethylene, mylar,or other suitable laminates. Alternatively, the dissection element 2300may include one or more layers of a first material, e.g., a urethanefilm, that are reinforced with one or more layers, strips, ribs, orother such portions of a second material, e.g., ripstop nylon orflashspun high-density polyethylene fibers.

With reference to FIG. 14 in particular, in the illustrated embodiment,the dissection element 2300 is formed from layers 2302 of material,e.g., layers 2302 _(A), 2302 _(B), that are secured together at one ormore junction points J, e.g., junction points J₁, J₂, through anysuitable manufacturing procedure, including, but not limited to, weldingusing impulse, laser, or RF, or through the use of an adhesive. Thedissection element 2300 is configured and formed to restrict expansionin a direction perpendicular to the junction points J₁, J₂, i.e., alongthe Y axis in the illustrated embodiment.

Although illustrated as being formed from multiple layers 2302 ofmaterial that are secured together at multiple junction points, i.e.,the aforedescribed junction points J_(i), J₂, it should be appreciatedthat the dissection element 2300 may also be formed from a single layer2302 of material secured to itself at single junction point, or at aplurality of junction points. For example, a single layer 2302 ofmaterial may be folded onto itself.

FIG. 15 illustrates another embodiment of the dissection element, whichis identified by the reference character 3300. The dissection element3300 is identical to the dissection element 2300 discussed above withrespect to FIGS. 12-14, but for the differences described below.

The dissection element 3300 includes layers 3302 of material, e.g.,layers 3302 _(A), 3302 _(B), 3302 _(C), 3302 _(D), that are securedtogether at junction points J₁, J₂, J₃, J₄. As discussed in connectionwith the dissection element 2300 illustrated in FIG. 14, the dissectionelement 3300 is configured and formed to restrict expansion indirections perpendicular to the junction points J₁, J₂, J₃, J₄. As such,in the embodiment illustrated in FIG. 15, the layers 3302 of materialrestrict expansion of the dissection element 3300 in multipledimensions, i.e., along the X and Y axes.

Persons skilled in the art will understand that the various apparatus,and corresponding methods of use described herein and shown in theaccompanying drawings, constitute non-limiting, exemplary embodiments ofthe present disclosure, and that additional components and features maybe added to any of the embodiments discussed herein above withoutdeparting from the scope of the present disclosure. For example, thevarious embodiments of the dissector assemblies described herein may bemodified to include a pressure sensor in order to monitor pressurewithin the various dissection elements, and/or an escape valve in orderto inhibit over expansion.

Additionally, persons skilled in the art will understand that theelements and features shown or described in connection with oneexemplary embodiment may be combined with those of another embodimentwithout departing from the scope of the present disclosure, and willappreciate further features and advantages of the presently disclosedsubject matter based on the above-described embodiments and the claims.Accordingly, the present disclosure is not limited by what has beenparticularly shown and described.

What is claimed is:
 1. A surgical apparatus configured and dimensionedto create an internal surgical worksite, the surgical apparatuscomprising: an expandable dissection element; and a restrictor incontact with the dissection element, the restrictor including a pair offirst arms and a pair of second arms, the pair of first arms beingsecured together, and the pair of second arms being secured together,such that the restrictor restricts expansion of the dissection elementin at least one direction.
 2. The surgical apparatus of claim 1, whereinthe restrictor is configured to restrict expansion of the dissectionelement such that the dissection element defines a generally planarconfiguration in the expanded condition.
 3. The surgical apparatus ofclaim 1, wherein the dissection element is formed from a first material,and the restrictor is formed from a second material different than thefirst material.
 4. The surgical apparatus of claim 3, wherein the firstmaterial has a first durometer, and the second material has a second,greater durometer.
 5. The surgical apparatus of claim 4, wherein thedissection element is formed from urethane, and the restrictor is formedfrom ripstop nylon.
 6. The surgical apparatus of claim 1, wherein thedissection element and the restrictor are configured as discretestructures.
 7. The surgical apparatus of claim 6, wherein the restrictoris positioned externally of the dissection element.
 8. The surgicalapparatus of claim 1, wherein the pair of first arms are weldedtogether, and the pair of second arms are welded together.
 9. Thesurgical apparatus of claim 6, wherein the restrictor is positionedinternally within the dissection element.
 10. The surgical apparatus ofclaim 6, wherein the restrictor is positioned between adjacent layers ofthe first material.
 11. The surgical apparatus of claim 1, wherein thedissection element and the restrictor are formed from the same material.12. The surgical apparatus of claim 11, wherein the dissection elementand the restrictor are monolithically formed.
 13. The surgical apparatusof claim 12, wherein the dissection element defines a first thickness,and the restrictor element defines a second, greater thickness.
 14. Thesurgical apparatus of claim 1, wherein the dissection element is atleast partially formed from a material permitting at least some light topass therethrough.
 15. A restrictor configured for use with anexpandable dissection element during creation of an internal surgicalworksite, the restrictor comprising: a first portion including a firstarm and a second arm; and a second portion connected to the firstportion, the second portion including a first arm and a second arm,wherein the first arm of the first portion is secured to the first armof the second portion, and the second arm of the first portion issecured to the second arm of the second portion, whereby the restrictorrestricts expansion of the dissection element in at least one direction.16. The restrictor of claim 15, wherein the restrictor is configured anddimensioned to restrict expansion of the dissection element such thatthe dissection element defines a planar configuration in the expandedcondition.
 17. The restrictor of claim 15, wherein the restrictor isless resilient than the dissection element.
 18. The restrictor of claim17, wherein the restrictor is formed from a first material, and thedissection element is formed from a second, different material, thefirst material having a higher durometer than the second material. 19.The restrictor of claim 18, wherein the dissection element is formedfrom urethane, and the restrictor is formed from ripstop nylon.
 20. Therestrictor of claim 15, wherein the first arm of the first portion iswelded to the first arm of the second portion, and the second arm of thefirst portion is welded to the second arm of the second portion.